Effect of the combustion system on reduction of thermal specific energy consumption in an industrial high temperature process

This paper presents an experimental study carried out in an industrial furnace for frits production using different configurations of burners based on different combustion techniques such as enriched air combustion, flat-flame oxy-combustion and preheater air combustion. The residence time of combustion gases inside the furnace also was modified. Several combustion configurations were tested and its effects on productivity and thermal energy specific consumption and efficiency were determined. The results show that higher residence time of the combustion gases can decrease significantly the specific consumption of fuel, while the change of the burners and combustion techniques did not show significant effects on decreasing the energy consumption. However, it is highlighted that the oxy-combustion flat-flame burners produced the lowest specific consumption of fuel. Even though the experiments were conducted in a furnace for frit production, the corresponding results can also be applied to guide or improve other industrial high temperature processes.

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Experimental Use of Microwaves in the High Temperature Foaming Process of Glass Waste to Manufacture Heat Insulating Material in Building Construction

Journal La Multiapp ◽

10.37899/journallamultiapp.v1i3.190 ◽

2020 ◽

Vol 1 (3) ◽

pp. 17-26

Author(s):

Lucian Paunescu ◽

Sorin Mircea Axinte ◽

Marius Florin Dragoescu ◽

Felicia Cosmulescu

Keyword(s):

Thermal Conductivity ◽

Energy Consumption ◽

High Temperature ◽

Specific Energy Consumption ◽

Coal Ash ◽

Building Construction ◽

Raw Material ◽

High Porosity ◽

Glass Waste ◽

Cellular Glass

Abstract The aim of the paper was the experimental manufacture of cellular glass from glass waste and coal ash as raw material and silicon carbide as a foaming agent, using the unconventional microwave heating technique. This heating technique, although known since the last century and recognized worldwide as fast and economical, is not yet industrially applied in high temperature thermal processes. The cellular glass manufacturing process requires high temperatures and the use of microwaves in this process is the originality of the work. The experiments aimed at producing thermal insulating materials with high porosity and low thermal conductivity for building construction similar in terms of quality to those manufactured industrially by conventional techniques, but with lower energy consumption. The obtained samples had adequate characteristics (apparent density 0.22-0.32 g/cm3, porosity 85.5-90.0%, thermal conductivity 0.043-0.060 W/m·K, compressive strength 1.23-1.34 MPa), and the specific energy consumption was low (0.84-0.89 kWh/kg). Theoretically, given the use of microwave equipment on an industrial scale, this consumption comparable in value to that industrially achieved by conventional techniques could decrease by up to 25%.

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Spruce fiber properties after high-temperature thermomechanical pulping (HT-TMP)

Holzforschung ◽

10.1515/hf-2013-0083 ◽

2014 ◽

Vol 68 (2) ◽

pp. 195-201 ◽

Cited By ~ 5

Author(s):

Iina Solala ◽

Toni Antikainen ◽

Mehedi Reza ◽

Leena-Sisko Johansson ◽

Mark Hughes ◽

...

Keyword(s):

Energy Consumption ◽

High Temperature ◽

Matrix Material ◽

Specific Energy Consumption ◽

Electrical Energy ◽

Strength Properties ◽

Thermomechanical Pulp ◽

Wall Region ◽

Fiber Properties ◽

Thermomechanical Pulping

Abstract Spruce was submitted to high-temperature (150°C–170°C) refining for 2 or 5 min to produce thermomechanical pulp (TMP) fibers with decreased electrical energy consumption. The pulp was characterized in terms of specific energy consumption as well as tensile and surface properties. The fibers from high-temperature TMP contained more surface lignin even if all sample types usually broke at the S1–S2 cell wall region. They also produced significantly weaker paper sheets, whereas their dry zero-span strength did not suffer substantial losses, indicating decreased fiber-fiber bonding. Tensile strength properties were also determined of a bisphenol-A-epichlorohydrin-based epoxy resin mixed with 5% fiber as a test for fiber-matrix compatibility in composite applications. Based on these preliminary results, high-temperature TMP shows potential for composite reinforcement due to its lower tendency to aggregate and its better compatibility with the tested matrix material.

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Thin Film Thickness and Uniformity Measurement for Lab-on-Chip Based Nanoelectrode Biosensor Development

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.832.95 ◽

2013 ◽

Vol 832 ◽

pp. 95-100

Author(s):

Balakrishnan Sharma Rao ◽

Uda Hashim ◽

Tijjani Adam

Keyword(s):

High Temperature ◽

Thermal Processing ◽

Chemical Vapor ◽

Wafer Surface ◽

Thin Film Thickness ◽

Lab On Chip ◽

High Temperature Process ◽

High Temperature Processes ◽

Pressure Chemical ◽

On Chip

One of the advantages of silicon substrate over other semiconductor substrate is the high temperature process capability of the silicon. In this work, silicon wafer is used for thermal processing which involves many high temperature processes such as oxidation and deposition. Thin films on the wafer surface are investigated for its thickness and uniformity. Silicon dioxide (SiO2) is initially grown using wet oxidation method and characterized for its thickness using FilmetricsSpectrometer. The thickness of SiO2 achieved is less than 300nm. Silicon Nitride (Si3N4) is then deposited by sputter method and its thickness is measured at 210 nm. For the electrode, polysilicon (PolySi) is deposited using Low Pressure Chemical Vapor Deposition (LPCVD) process. Silane (SiH4) is used as the source forPolySi deposition and the thickness is measured at 160nm. Standard deviation is calculated based on the layer thickness and the uniformity is checked across 5 points on the wafer. Hence, it is very important to have a uniform layer across the wafer surface for a defect free device and at the same time it protects the sensitivity of the sensor.

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Optimization of process variables for briquetting of biochar from corn stover

BioResources ◽

10.15376/biores.15.3.6811-6825 ◽

2020 ◽

Vol 15 (3) ◽

pp. 6811-6825

Author(s):

Wenqiao Jiao ◽

Lope Galindo Tabil ◽

Mingjin Xin ◽

Yuqiu Song ◽

Bowen Chi ◽

...

Keyword(s):

Energy Consumption ◽

Moisture Content ◽

Corn Stover ◽

Residence Time ◽

Specific Energy ◽

Dimensional Stability ◽

Specific Energy Consumption ◽

Mean Values ◽

Set Up ◽

Experimental Values

Instead of compressing biomass into briquettes, this study considers the compression of biochar. Densification is necessary for biochar to increase bulk density for convenience of handling, transportation, and storage. Response surface methodology was employed, and briquetting of biochar from corn stover was carried out in this study to investigate the effects of moisture content (at levels of 16, 17.6, 20, 22.4, and 24%), pressure (at levels of 21.5, 25, 30, 35, and 38.5 MPa), and residence time (at levels of 4, 6.4, 10, 13.6, and 16 s), on crushing resistance, dimensional stability of briquettes, and specific energy consumption of briquetting. The results showed that the effects of the variables on each evaluation index were significant (P < 0.01), the influence order was obtained, and the regression models are set up. The optimum condition for the briquetting process was moisture content of 18.5%, pressure of 38.5 MPa, and residence time of 4 s, giving mean values of the briquette crushing resistance of 49.9 N, dimensional stability of 93.8%, and specific energy consumption of briquetting of 4.41 MJ/t, respectively. The errors between the predicted values and the experimental values are all less than 5%.

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RECYCLING OF FERROUS METAL SHAVINGS

Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY) ◽

10.21122/1683-6065-2017-4-94-101 ◽

2018 ◽

pp. 94-101

Author(s):

S. L. Rovin ◽

L. E. Rovin ◽

T. M. Zayac ◽

O. M. Valickaya

Keyword(s):

Energy Consumption ◽

High Temperature ◽

Cost Reduction ◽

Specific Energy Consumption ◽

Ferrous Metal ◽

Waste Generation ◽

Iron And Steel ◽

Ferrous Metals ◽

Rotary Kilns ◽

Chips Recycling

The most advanced and universal way of chips recycling of ferrous metals is the technology of direct chips remelting in rotational tilting furnaces (RBF) directly at the enterprises-sources of waste generation. However common practice of iron and steel chips recycling is based on its briquetting and subsequent remelting in traditional furnaces.For cost reduction when chip briquetting and organization of hot briquetting sections in places of its formation highly efficient equipment – rotational dryer and RBF is proposed. The possibility and effectiveness of developed furnaces for lowand high-temperature chip heating in briquetting lines is proved. Thermal efficiency of such furnaces when dispersed materials heating is much higher than drum or feed-through furnaces. Hot briquetting of shavings reduces the pressing force, which reduces the specific energy consumption. The use of rotary kilns can reduce technological operations and equipment of production sites for the manufacture of briquettes

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Simulation Based Studies of Energy Saving Measures in the Aluminum Tool and Die Casting Industry

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.856.131 ◽

2016 ◽

Vol 856 ◽

pp. 131-139 ◽

Cited By ~ 2

Author(s):

Matthias Henninger ◽

Wolfgang Schlüter ◽

Dominik Jeckle ◽

Jörg Schmidt

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

High Temperature ◽

Specific Energy ◽

Flue Gas ◽

Die Casting ◽

Operation Mode ◽

Specific Energy Consumption ◽

Manufacturing Plant ◽

Furnace Charge

This study, which focuses on analyzing aluminum melting and die casting procedures is part of the Smart Melting project in the research network Green Factory Bavaria (GFB). The aim of the present research project is to investigate these procedures and to suggest measures to increase the overall energy efficiency. The analysis starts with the capture of the operating structure, the relations between supply and consumption of liquid aluminum and an evaluation of aluminum furnaces themselves. The study concentrates on shaft furnaces whose specific energy consumption is 25 % higher than stated by the manufacturers. At the same time the melting capacity of the furnaces ranges at the lower end according to the manufacturer's data. The reason for this deviation is a discontinuous operation mode due to demand fluctuations. Consequently the flue gas has still a high temperature which means a high waste of energy. Based on these facts the furnace charge and operation mode have to be optimized and the high temperature flue gas can be used to preheat the pig aluminum.A numerical model of aluminum furnaces is applied to investigate this optimization potential. This model can simulate either a single aluminum furnace (case 1) or a furnace integrated in the entire manufacturing plant (case 2). The advantage of case 1 is the furnace's operation on its most efficient point because there is no influence of the die casting process. In case 1 an improvement of the furnace charge leads to a higher capacity utilization and therefore to a reduction of 30 % specific energy consumption and a 50 % increase of melting capacity. Whereas in case 2 the simulation of the entire manufacturing plant results in a rise of 25 % melting capacity and a 16 % decrease of specific energy consumption. The simulation proved increasing energy efficiency due to preheating the pig aluminum in both cases.

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